178 research outputs found

    Medieval Glassworks in the City of Ferrara (North Eastern Italy): The Case Study of Piazza Municipale

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    Compositional and structural characterization was carried out on transparent glass fragments found in a brick rubbish pit discovered in basal floor of the ducal palace of Ferrara, during the excavation of Piazza Municipale. This study aims to identify raw materials and glass-working techniques through X-Ray Fluorescence (XRF) quantitative chemical analyses and semi-quantitative Scanning Electron Microscopy (SEM) observations. The studied fragments were produced using siliceous-lime sands with natron as flux, and allowed us to better understand the production technologies in a historical period of great innovation for European glass art. The numerous findings of glass fragments discovered in brick underground cellars built for the specific purpose of household rubbish of wealthy complexes in Ferrara testify a consolidated system of separate discharge of solid waste into underground containers, which were closed and sealed once filled. The high volume of the finds indicates the absence of recycling of accumulated materials due to the well-being of the city. Compositional analysis confirmed the local production of glass shops in Ferrara during the late Middle Ages, characterized by differences with the glasses of the nearby city of Venice. Morphological analyses also defined the nature and relative abundance of the products, exploring the types and compositions of the Ferrara glass art

    ASSESSMENT OF THE TOTAL SOLIDS AND FAT CONTENTS IN WHOLE LIQUID EGG PRODUCTS BY ELECTRICAL AND THERMAL CONDUCTIVITY MEASUREMENTS

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    The total solids and fat contents of nine whole liquid egg products were assessed by means of electrical and thermal conductivity measurements. Linear correlations between conductivity values and total solids and fat contents were obtained with R2 values up to 0.995 and 0.990 and maximum errors of predic- 46 TABLE 6 - Linear regression models for the total solids (TS, %) and fat (FC, %) contents estimation from electrical (Ec, mS/cm) and thermal (Tc, W/mK) conductivity measurements. SE: Standard Error. Linear regression equation R2 p-level SE (%) TS=-6.857*Ec+65.373 0.995 0.000 0.27 FC=-4.993*Ec+40.070 0.985 0.000 0.33 TS=-172.967*Tc+109.605 0.992 0.000 0.33 FC=-126.449*Tc+72.521 0.990 0.000 0.27 tion up to 0.41% and 0.42%, respectively. The electrical conductivity of the albumen, yolk and egg mixtures linearly increased with temperature; at 20°C, temperature coefficients of 2.1%/°C, 2.1%/°C and 1.9 %/°C were respectively calculated. On the contrary, the thermal conductivity of the analysed products did not appear to be substantially influenced by the temperature of the liquid

    NUMERICAL SIMULATION OF PHYSICAL SYSTEMS IN AGRI-FOOD ENGINEERING

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    In agri-food engineering many complex problems arise in plant and process design. Specifically the designer has to deal with fluid dynamics, thermal or mechanical problems, often characterized by physics coupling, non-linearity, irregular geometry, anisotropy and in definitive rather high complexity. In recent years, the ever growing availability of computational power at low cost, made these problems more often approached with numerical simulation techniques. Mainly in terms of finite elements and finite volumes. In this paper the fundamentals of numerical methods are briefly recalled and a discussion about their possibility of application in the food and agricultural engineering is developed

    Numerical models of mass transfer during ripening and storage of salami

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    Ripening, in the dry sausages manufacturing process, has an influence over the main physical, chemical and microbiological transformations that take place inside these products and that define the final organoleptic properties of dry sausages. A number of study about the influence of ripening conditions on the main chemical and microbiological characteristics of dry sausages is available today. All these studies indicate that the final quality and safety standards achieved by the sausage manufacturing process can be considered to be strictly dependent from the specific ripening conditions. The water diffusion inside a seasoned sausage is surely an aspect of primary importance with regard to the quality of final product. As a consequence the aim of this research was to develop two parametric numerical models, concerning the moisture diffusion physics, describing salami ripening and storage. Mass transfer equations inside the sausage volume were numerically solved using a finite element technique. A first model describes diffusion phenomena occurring inside the salami and the exchange phenomena involving the surface of the product and the environment. After the ripening, the salami are stored in waterproof packaging, consequently an additional model able to describe also the evaporation and condensation phenomena occurring between the salami surface and the air in the package, was developed. The moisture equilibrium between salami surface and conservation atmosphere is mainly ruled by the temperature changes during storage. Both models allow to analyze the history of the moisture content inside the salami and are parametrised on product size and maturation/storage conditions. The models were experimentally validated, comparing the numerical outputs of the simulations with experimental data, showing a good agreement

    Theoretical and experimental study on mechanical characterisation of a water drop impact on a solid surface

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    The drop impact phenomenon can be used to study many agricultural aspects related to the rainfall, runoff and irrigation, such as the stability of aggregated and the detachment of fine particles. The aim of this study was to study experimentally and numerically the water drop impact on a solid wall. In a first phase a simple experimental apparatus and basic theoretical concepts were used to investigate the influence of the drop speed on the impact pressure. In the second section, a finite element model able to reproduce the complex phenomenon observed in the experimental phase, was developed. The pressure values obtained by experimental measurement are similar to those calculated on the base of the energy conservation principle (average percentage difference of 15.6%). Numerical model was useful to obtain important information on pressure profile inside the drop and the impact pressure during the splash, at present hard to achieve experimentally. The model was used to estimate also an almost realistic dynamic behaviour of the spreading drop

    Screening of grated cheese authenticity by nir spectroscopy

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    Parmigiano–Reggiano (PR) cheese is one of the oldest traditional cheeses produced in Europe, and it is still one of the most valuable Protected Designation of Origin (PDO) cheeses of Italy. The denomination of origin is extended to the grated cheese when manufactured exclusively from whole Parmigiano-Reggiano cheese wheels that respond to the production standard. The grated cheese must be matured for a period of at least 12 months and characterized by a rind content not over 18%. In this investigation the potential of near infrared spectroscopy (NIR), coupled to different statistical methods, were used to estimate the authenticity of grated Parmigiano Reggiano cheese PDO. Cheese samples were classified as: compliance PR, competitors, non-compliance PR (defected PR), and PR with rind content greater then 18%. NIR spectra were obtained using a spectrophotometer Vector 22/N (Bruker Optics, Milan, Italy) in the diffuse reflectance mode. Instrument was equipped with a rotating integrating sphere. Principal Component Analysis (PCA) was conducted for an explorative spectra analysis, while the Artificial Neural Networks (ANN) were used to classify spectra, according to different cheese categories. Subsequently the rind percentage and month of ripening were estimated by a Partial Least Squares regression (PLS). Score plots of the PCA show a clear separation between compliance PR samples and the rest of the sample was observed. Competitors samples and the defected PR samples were grouped together. The classification performance for all sample classes, obtained by ANN analysis, was higher of 90%, in test set validation. Rind content and month of ripening were predicted by PLS a with a determination coefficient greater then 0.95 (test set). These results showed that the method can be suitable for a fast screening of grated cheese authenticity

    nectar defense and hydrogen peroxide in floral nectar of cucurbita pepo

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    This study was carried out to investigate some similarities between the nectaries of Nicotiana sp. and Cucurbita pepo, such as starch accumulation in the nectary parenchyma, changes in nectary color during maturation, and the production of a large quantity of sucrose-dominant nectar. The concentration of hydrogen peroxide in C. pepo floral nectar was determined in order to verify the presence of a defense mechanism similar to that found in Nicotiana sp. which protects nectar from yeast and bacteria proliferation. We also tested the eventual accumulation of antioxidants in the nectary of C. pepo as a protection against oxidative stress caused by hydrogen peroxide. The level of hydrogen peroxide found in the floral nectar of C. pepo was much lower than that found in Nicotiana sp. and the male flowers of Cucurbita had a higher concentration than the female flowers. The low oxidative stress induced by this level of hydrogen peroxide caused the accumulation of a low amount of lutein inside the plastoglobules which were contained in amyloplasts. Plastids of the C. pepo nectary are specialized in the accumulation of starch rather than antioxidants

    Geosynchronous SAR for Terrain & atmosphere with short revisit (GeoSTARe)

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    Geo STA Re would be a mission combining the continuous view capabilities from geostationary orbits of super-continental areas with the all-day, all-weather imaging capabilities of Synthetic Aperture Radar. It would complement Copernicus Sentinel-1 bringing the repeat time from days down to hours. In that, it would provide novel and unique observations. The well proven potentials of Radar in sensing roughness, deformations, and moisture, combined with the short time to get any image, from minutes to an hour, and the immediate data download and exploitation (thanks to the geostationary orbit) makes GeoSTARe a game changer in those fields where hourly-to-daily monitoring is a must

    Re-determination of the primary shelf-life of food products: what are the guarantees for the consumer?

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    Except in rare cases, the determination of the shelf-life of food products is left up to the food business operator. The extension of this period, which for years has been the subject of debate among the various actors in the food chain, has become a topic of fundamental importance also following the recent economic/financial, environmental, and health crises, which have had an inevitable impact on consumption and food waste. While there is no requirement to indicate durability for some categories of food products, for example, those not directly intended for consumers, this debate has raised questions and perplexities about the potential reevaluation of the origin conditions established by the manufacturer, particularly when it comes to maintaining the guarantees for the consumer in terms of health and hygiene. In addition, the increasing consumer demand for accurate information has prompted the European authorities to request a public consultation on the actual understanding and perception of the mandatory terms on labels such as use by or date of minimum durability of a food, provided for by Article 9 of Regulation (EU) No. 1169/2011, often not correctly understood, which can assume great significance in the application of rules to reduce food waste. In this regard, it is useful to remember that the recent measures adopted by the European Union legislator, together with the case law of recent years, have led the judges of merit to comply with the principles and requirements of food safety laid down since 2002 in Regulation (EC) No. 178, thus paying greater attention to the analysis, assessment, and management of the risk of the entire production chain. The purpose of this work is to provide technical-legal elements to encourage a possible extension of the shelf-life of food products while ensuring the safety of consumers

    Intravenous immunoglobulin therapy in the treatment of the acute phase of chronic idiopathic thrombocytopenic purpura in adults

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    A prospective, open-label phase III study was carried out to evaluate the efficacy and tolerability of a preparation of virus-inactivated normal human intravenous immunoglobulin. Fifteen adult patients suffering from chronic idiopathic thrombocytopenic purpura (ITP), (basal platelet count <20x109/l), received 0.4 g/kg daily for 5 days. The increase in platelet count, reduction in hemorrhagic events, duration of platelet response, and incidence of adverse events were recorded. Fourteen out of 15 patients achieved a platelet count ?50x109/l (response rate was 93.3%), and only 2 out of 10 patients with positive baseline Rumple-Leed test remained positive after treatment (p =0.0022). Interestingly, a close inverse correlation between platelet counts and haemoglobin levels was observed. No side effects were recorded. This study provides evidence of therapeutic efficacy and the good tolerability of the immunoglobulin preparation we used in this trial, and suggests the role of haemolysis as a mechanism for the increase in platelet count
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